Mix/Src/maildir.c

/* Mixmaster version 3.0  --  (C) 1999 - 2004 Anonymizer Inc. and others.

   Mixmaster may be redistributed and modified under certain conditions.
   This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF
   ANY KIND, either express or implied. See the file COPYRIGHT for
   details.

   Maildir support routines
   $Id: $ */


/* Maildir support for Mixmaster 3 - see
   http://www.qmail.org/man/man5/maildir.html and
   http://cr.yp.to/proto/maildir.html

   Added by and (C) 2001 Doobee R. Tzeck 
   drt@un.bewaff.net - http://c0re.jp/

   To test it try:
   $ gcc maildir.c -DUNITTEST -o test_maildir
   $ ./test_maildir
   this should print a single line saying "OK"
*/

#include "mix3.h"

#ifdef WIN32
#include <io.h>
#include <direct.h>
#include <process.h>
#define sleep(s) Sleep(s*1000)
#define S_IWUSR _S_IWRITE
#define S_IRUSR _S_IREAD
#else /* end of WIN32 */
#include <unistd.h>
#endif /* else not WIN32 */
#include <fcntl.h>
#include <time.h>
#include <string.h>
#include <sys/stat.h>
#include <sys/types.h>
#include <errno.h>
#include <stdarg.h>
#include <assert.h>

#if defined(S_IFDIR) && !defined(S_ISDIR)
#define S_ISDIR(m) (((m) & S_IFMT) == S_IFDIR)
#endif /* defined(S_IFDIR) && !defined(S_ISDIR) */

#ifndef SHORTNAMES

static unsigned long namecounter = 0;

int checkDirectory(char *dir, char *append, int create) {
  char tmp[PATHMAX];
  struct stat buf;
  int err;

  tmp[0] = '\0';
  strcatn(tmp, dir, PATHMAX);
  if (append)
    strcatn(tmp, append, PATHMAX);

  err = stat(tmp, &buf);
  if (err == -1) {
    if (create) {
#ifndef POSIX
      err = mkdir(tmp);
#else /* end of not POSIX */
      err = mkdir(tmp, S_IRWXU);
#endif /* else if POSIX */
      if (err == 0)
        errlog(NOTICE, "Creating directory %s.\n", tmp);
    } else
      err = 1;
  } else if (!S_ISDIR(buf.st_mode))
    err = -1;

  return err;
}

/* Write "message" to "maildir", retunr 0 on success, -1 on failure */
#define MAX_BASENAME 113 /* actual length should be smaller than 111 bytes */
#define MAX_SUBNAME 123 /* actual length should be smaller than 115 bytes */
int maildirWrite(char *maildir, BUFFER *message, int create) {
  int fd;
  int count;
  int returnValue;
  char hostname[64];
  struct stat statbuf;
  char basename[MAX_BASENAME];
  char tmpname[MAX_SUBNAME];
  char newname[MAX_SUBNAME];
  int messagesize;
  char olddirectory[PATHMAX] = "";
  char normalizedmaildir[PATHMAX];

  /* Declare a handler for SIGALRM so we can time out. */
  /* set_handler(SIGALRM, alarm_handler);  */
  /* alarm(86400); */

  hostname[0] = '\0';
  gethostname(hostname, 63);
  hostname[63] = '\0';

  mixfile(normalizedmaildir, maildir);
  if ((checkDirectory(normalizedmaildir, NULL, create) != 0) ||
      (checkDirectory(normalizedmaildir, "tmp", create) != 0) ||
      (checkDirectory(normalizedmaildir, "cur", create) != 0) ||
      (checkDirectory(normalizedmaildir, "new", create) != 0)) {
    returnValue = -1;
    goto realend;
  }

  messagesize = message->length;

  /* Step 1: chdir to maildir (and save current dir) */
  if (getcwd(olddirectory, PATHMAX) == NULL) {
    returnValue = -1;
    goto realend;
  }
  olddirectory[PATHMAX-1] = '\0';
  if(chdir(normalizedmaildir) != 0) {
    returnValue = -1;
    goto functionExit;
  }

  /* Step 2:  Stat the temporary file.  Wait for ENOENT as a response. */
  for (count = 0;; count++) {
    tmpname[0] = '\0';
    newname[0] = '\0';
    snprintf(basename, MAX_BASENAME, "%lu.%u_%lu.%s,S=%u",
      time(NULL), getpid(), namecounter++, hostname, messagesize);
    basename[MAX_BASENAME-1] = '\0';
    strcatn(tmpname, "tmp" DIRSEPSTR, MAX_SUBNAME);
    strcatn(tmpname, basename, MAX_SUBNAME);
    strcatn(newname, "new" DIRSEPSTR, MAX_SUBNAME);
    strcatn(newname, basename, MAX_SUBNAME);

    if (stat(tmpname, &statbuf) == 0)
      errno = EEXIST;
    else if (errno == ENOENT) {
      /* Step 4: create the file (at least try) */
      fd = open(tmpname, O_WRONLY|O_CREAT|O_EXCL, S_IWUSR|S_IRUSR);
      if (fd >= 0)
        break; /* we managed to open the file */
    }

    if (count > 5) {
      /* Too many retries - give up */
      errlog(ERRORMSG, "Can't create message in %s\n", maildir);
      returnValue = -1;
      goto functionExit;
    }

    /* Step 3: sleep and retry */
    sleep(2);
  }

  /* Step 5:  write file */
  if(write(fd, message->data, message->length) != message->length) {
    returnValue = -1;
    goto functionExit;
  }

  /* on NFS this could fail */
#ifndef WIN32
  if((fsync(fd) != 0) || (close(fd) != 0)) {
#else /* end of not WIN32 */
  if((_commit(fd) != 0) || (close(fd) != 0)) {
#endif /* else if WIN32 */
    returnValue = -1;
    goto functionExit;
  }

  /* Step 6: move message to 'cur' */
#ifdef POSIX
  for (count = 0;; count++) {
    if(link(tmpname, newname) != 0) {
      if (errno == EXDEV || errno == EPERM) {
        /* We probably are on coda or some other filesystem that does not allow
         * hardlinks. rename() the file instead of link() and unlink()
         * I know, It's evil (PP).
         */
        if (rename(tmpname, newname) != 0) {
          returnValue = -1;
          goto functionExit;
        };
        break;
      } else if (errno != EEXIST) {
        returnValue = -1;
        goto functionExit;
      }
    } else {
      /* We successfully linked the message in new/. Now let's get
       * rid of our tmp/ entry
       */
      if(unlink(tmpname) != 0) {
        /* unlinking failed */
        returnValue = -1;
        goto functionExit;
      }
      break;
    }

    if (count > 5) {
      /* Too many retries - give up */
      errlog(ERRORMSG, "Can't move message to %s/new/\n", maildir);
      returnValue = -1;
      goto functionExit;
    }

    sleep(2);
    newname[0] = '\0';
    snprintf(basename, MAX_BASENAME, "%lu.%u_%lu.%s,S=%u",
      time(NULL), getpid(), namecounter++, hostname, messagesize);
    basename[MAX_BASENAME-1] = '\0';
    strcatn(newname, "new" DIRSEPSTR, MAX_SUBNAME);
    strcatn(newname, basename, MAX_SUBNAME);
  }
#else /* end of POSIX */
  /* On non POSIX systems we simply use rename(). Let's hope DJB
   * never finds out
   */
  if (rename(tmpname, newname) != 0) {
    returnValue = -1;
    goto functionExit;
  };
#endif /* else if not POSIX */

  returnValue = 0;

functionExit:
  /* return to original directory */
  assert(olddirectory[0] != '\0');
  if(chdir(olddirectory) != 0)
    returnValue = -1;

realend:

  return returnValue;
}

#else /* end of SHORTNAMES */
int maildirWrite(char *maildir, BUFFER *message, int create) {
{
  errlog(ERRORMSG, "Maildir delivery does not work with SHORTNAMES.\n");
  return -1;
}
#endif /* else if not SHORTNAMES */


#ifdef UNITTEST

#ifdef NDEBUG
#undef NDEBUG
#endif /* NDEBUG */

#include <dirent.h>

/* mock-up of errlog for unittest */
void errlog(int type, char *fmt,...)
{
  va_list ap;

  va_start(ap, fmt);
  vfprintf(stderr, fmt, ap);
  va_end(ap);
}

/* main for unittest */
int main()
{
  int i, count = 23;
  int fd;
  DIR *d;
  struct dirent *de;
  BUFFER message;
  char text[] = "From: nobody@un.bewaff.net\nTo: hackers@c0re.jp\nSubject: testing\n\nthis is just a test\n";
  char buf[1024];

  /* create buffer with test data */
  message.data = text;
  message.length = strlen(text);

  /* write <count> messages to maildir */
  for(i = 0; i < count; i++)
    assert(maildirWrite("Maildir.test_maildir", message, 1) == 0);

  /* read them back */
  assert((d = opendir("Maildir.test_maildir/new")) != NULL);
  for (i = 0; i < count + 2; i++)
    {
      de = readdir(d);
      if(de->d_name[0] != '.')
        {
          buf[0] = '\0';
          strcat(buf, "Maildir.test_maildir/new/");
          strcat(buf, de->d_name);
          fd = open(buf, O_RDONLY);
          assert(unlink(buf) == 0);
          assert(read(fd, buf, strlen(text)) == strlen(text));
          buf[strlen(text)] = '\0';
          /* check if they match the original message */
          assert(strcmp(text, buf) == 0);
          close(fd);
        }
    }

  /* no files left in directory? */
  assert(readdir(d) == NULL);

  /* delete maildir */
  assert(rmdir("Maildir.test_maildir/tmp") == 0);
  assert(rmdir("Maildir.test_maildir/new") == 0);
  assert(rmdir("Maildir.test_maildir/cur") == 0);
  assert(rmdir("Maildir.test_maildir") == 0);

  /* check if writing to a non existant maildir yilds an error */
  assert(maildirWrite("Maildir.test_maildir", &message, 0) == -1);

  puts("OK");
}
#endif /* UNITTEST */
1	/* Mixmaster version 3.0 -- (C) 1999 - 2004 Anonymizer Inc. and others.
2
3	Mixmaster may be redistributed and modified under certain conditions.
4	This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF
5	ANY KIND, either express or implied. See the file COPYRIGHT for
6	details.
7
8	Maildir support routines
9	$Id: $ */
10
11
12	/* Maildir support for Mixmaster 3 - see
13	http://www.qmail.org/man/man5/maildir.html and
14	http://cr.yp.to/proto/maildir.html
15
16	Added by and (C) 2001 Doobee R. Tzeck
17	drt@un.bewaff.net - http://c0re.jp/
18
19	To test it try:
20	$ gcc maildir.c -DUNITTEST -o test_maildir
21	$ ./test_maildir
22	this should print a single line saying "OK"
23	*/
24
25	#include "mix3.h"
26
27	#ifdef WIN32
28	#include <io.h>
29	#include <direct.h>
30	#include <process.h>
31	#define sleep(s) Sleep(s*1000)
32	#define S_IWUSR _S_IWRITE
33	#define S_IRUSR _S_IREAD
34	#else /* end of WIN32 */
35	#include <unistd.h>
36	#endif /* else not WIN32 */
37	#include <fcntl.h>
38	#include <time.h>
39	#include <string.h>
40	#include <sys/stat.h>
41	#include <sys/types.h>
42	#include <errno.h>
43	#include <stdarg.h>
44	#include <assert.h>
45
46	#if defined(S_IFDIR) && !defined(S_ISDIR)
47	#define S_ISDIR(m) (((m) & S_IFMT) == S_IFDIR)
48	#endif /* defined(S_IFDIR) && !defined(S_ISDIR) */
49
50	#ifndef SHORTNAMES
51
52	static unsigned long namecounter = 0;
53
54	int checkDirectory(char dir, char append, int create) {
55	char tmp[PATHMAX];
56	struct stat buf;
57	int err;
58
59	tmp[0] = '\0';
60	strcatn(tmp, dir, PATHMAX);
61	if (append)
62	strcatn(tmp, append, PATHMAX);
63
64	err = stat(tmp, &buf);
65	if (err == -1) {
66	if (create) {
67	#ifndef POSIX
68	err = mkdir(tmp);
69	#else /* end of not POSIX */
70	err = mkdir(tmp, S_IRWXU);
71	#endif /* else if POSIX */
72	if (err == 0)
73	errlog(NOTICE, "Creating directory %s.\n", tmp);
74	} else
75	err = 1;
76	} else if (!S_ISDIR(buf.st_mode))
77	err = -1;
78
79	return err;
80	}
81
82	/* Write "message" to "maildir", retunr 0 on success, -1 on failure */
83	#define MAX_BASENAME 113 /* actual length should be smaller than 111 bytes */
84	#define MAX_SUBNAME 123 /* actual length should be smaller than 115 bytes */
85	int maildirWrite(char maildir, BUFFER message, int create) {
86	int fd;
87	int count;
88	int returnValue;
89	char hostname[64];
90	struct stat statbuf;
91	char basename[MAX_BASENAME];
92	char tmpname[MAX_SUBNAME];
93	char newname[MAX_SUBNAME];
94	int messagesize;
95	char olddirectory[PATHMAX] = "";
96	char normalizedmaildir[PATHMAX];
97
98	/* Declare a handler for SIGALRM so we can time out. */
99	/* set_handler(SIGALRM, alarm_handler); */
100	/* alarm(86400); */
101
102	hostname[0] = '\0';
103	gethostname(hostname, 63);
104	hostname[63] = '\0';
105
106	mixfile(normalizedmaildir, maildir);
107	if ((checkDirectory(normalizedmaildir, NULL, create) != 0) \|\|
108	(checkDirectory(normalizedmaildir, "tmp", create) != 0) \|\|
109	(checkDirectory(normalizedmaildir, "cur", create) != 0) \|\|
110	(checkDirectory(normalizedmaildir, "new", create) != 0)) {
111	returnValue = -1;
112	goto realend;
113	}
114
115	messagesize = message->length;
116
117	/* Step 1: chdir to maildir (and save current dir) */
118	if (getcwd(olddirectory, PATHMAX) == NULL) {
119	returnValue = -1;
120	goto realend;
121	}
122	olddirectory[PATHMAX-1] = '\0';
123	if(chdir(normalizedmaildir) != 0) {
124	returnValue = -1;
125	goto functionExit;
126	}
127
128	/* Step 2: Stat the temporary file. Wait for ENOENT as a response. */
129	for (count = 0;; count++) {
130	tmpname[0] = '\0';
131	newname[0] = '\0';
132	snprintf(basename, MAX_BASENAME, "%lu.%u_%lu.%s,S=%u",
133	time(NULL), getpid(), namecounter++, hostname, messagesize);
134	basename[MAX_BASENAME-1] = '\0';
135	strcatn(tmpname, "tmp" DIRSEPSTR, MAX_SUBNAME);
136	strcatn(tmpname, basename, MAX_SUBNAME);
137	strcatn(newname, "new" DIRSEPSTR, MAX_SUBNAME);
138	strcatn(newname, basename, MAX_SUBNAME);
139
140	if (stat(tmpname, &statbuf) == 0)
141	errno = EEXIST;
142	else if (errno == ENOENT) {
143	/* Step 4: create the file (at least try) */
144	fd = open(tmpname, O_WRONLY\|O_CREAT\|O_EXCL, S_IWUSR\|S_IRUSR);
145	if (fd >= 0)
146	break; /* we managed to open the file */
147	}
148
149	if (count > 5) {
150	/* Too many retries - give up */
151	errlog(ERRORMSG, "Can't create message in %s\n", maildir);
152	returnValue = -1;
153	goto functionExit;
154	}
155
156	/* Step 3: sleep and retry */
157	sleep(2);
158	}
159
160	/* Step 5: write file */
161	if(write(fd, message->data, message->length) != message->length) {
162	returnValue = -1;
163	goto functionExit;
164	}
165
166	/* on NFS this could fail */
167	#ifndef WIN32
168	if((fsync(fd) != 0) \|\| (close(fd) != 0)) {
169	#else /* end of not WIN32 */
170	if((_commit(fd) != 0) \|\| (close(fd) != 0)) {
171	#endif /* else if WIN32 */
172	returnValue = -1;
173	goto functionExit;
174	}
175
176	/* Step 6: move message to 'cur' */
177	#ifdef POSIX
178	for (count = 0;; count++) {
179	if(link(tmpname, newname) != 0) {
180	if (errno == EXDEV \|\| errno == EPERM) {
181	/* We probably are on coda or some other filesystem that does not allow
182	* hardlinks. rename() the file instead of link() and unlink()
183	* I know, It's evil (PP).
184	*/
185	if (rename(tmpname, newname) != 0) {
186	returnValue = -1;
187	goto functionExit;
188	};
189	break;
190	} else if (errno != EEXIST) {
191	returnValue = -1;
192	goto functionExit;
193	}
194	} else {
195	/* We successfully linked the message in new/. Now let's get
196	* rid of our tmp/ entry
197	*/
198	if(unlink(tmpname) != 0) {
199	/* unlinking failed */
200	returnValue = -1;
201	goto functionExit;
202	}
203	break;
204	}
205
206	if (count > 5) {
207	/* Too many retries - give up */
208	errlog(ERRORMSG, "Can't move message to %s/new/\n", maildir);
209	returnValue = -1;
210	goto functionExit;
211	}
212
213	sleep(2);
214	newname[0] = '\0';
215	snprintf(basename, MAX_BASENAME, "%lu.%u_%lu.%s,S=%u",
216	time(NULL), getpid(), namecounter++, hostname, messagesize);
217	basename[MAX_BASENAME-1] = '\0';
218	strcatn(newname, "new" DIRSEPSTR, MAX_SUBNAME);
219	strcatn(newname, basename, MAX_SUBNAME);
220	}
221	#else /* end of POSIX */
222	/* On non POSIX systems we simply use rename(). Let's hope DJB
223	* never finds out
224	*/
225	if (rename(tmpname, newname) != 0) {
226	returnValue = -1;
227	goto functionExit;
228	};
229	#endif /* else if not POSIX */
230
231	returnValue = 0;
232
233	functionExit:
234	/* return to original directory */
235	assert(olddirectory[0] != '\0');
236	if(chdir(olddirectory) != 0)
237	returnValue = -1;
238
239	realend:
240
241	return returnValue;
242	}
243
244	#else /* end of SHORTNAMES */
245	int maildirWrite(char maildir, BUFFER message, int create) {
246	{
247	errlog(ERRORMSG, "Maildir delivery does not work with SHORTNAMES.\n");
248	return -1;
249	}
250	#endif /* else if not SHORTNAMES */
251
252
253	#ifdef UNITTEST
254
255	#ifdef NDEBUG
256	#undef NDEBUG
257	#endif /* NDEBUG */
258
259	#include <dirent.h>
260
261	/* mock-up of errlog for unittest */
262	void errlog(int type, char *fmt,...)
263	{
264	va_list ap;
265
266	va_start(ap, fmt);
267	vfprintf(stderr, fmt, ap);
268	va_end(ap);
269	}
270
271	/* main for unittest */
272	int main()
273	{
274	int i, count = 23;
275	int fd;
276	DIR *d;
277	struct dirent *de;
278	BUFFER message;
279	char text[] = "From: nobody@un.bewaff.net\nTo: hackers@c0re.jp\nSubject: testing\n\nthis is just a test\n";
280	char buf[1024];
281
282	/* create buffer with test data */
283	message.data = text;
284	message.length = strlen(text);
285
286	/* write <count> messages to maildir */
287	for(i = 0; i < count; i++)
288	assert(maildirWrite("Maildir.test_maildir", message, 1) == 0);
289
290	/* read them back */
291	assert((d = opendir("Maildir.test_maildir/new")) != NULL);
292	for (i = 0; i < count + 2; i++)
293	{
294	de = readdir(d);
295	if(de->d_name[0] != '.')
296	{
297	buf[0] = '\0';
298	strcat(buf, "Maildir.test_maildir/new/");
299	strcat(buf, de->d_name);
300	fd = open(buf, O_RDONLY);
301	assert(unlink(buf) == 0);
302	assert(read(fd, buf, strlen(text)) == strlen(text));
303	buf[strlen(text)] = '\0';
304	/* check if they match the original message */
305	assert(strcmp(text, buf) == 0);
306	close(fd);
307	}
308	}
309
310	/* no files left in directory? */
311	assert(readdir(d) == NULL);
312
313	/* delete maildir */
314	assert(rmdir("Maildir.test_maildir/tmp") == 0);
315	assert(rmdir("Maildir.test_maildir/new") == 0);
316	assert(rmdir("Maildir.test_maildir/cur") == 0);
317	assert(rmdir("Maildir.test_maildir") == 0);
318
319	/* check if writing to a non existant maildir yilds an error */
320	assert(maildirWrite("Maildir.test_maildir", &message, 0) == -1);
321
322	puts("OK");
323	}
324	#endif /* UNITTEST */